Basics: BadgerCare covers 1,059,834 humans
Wisconsin is a state that expanded income eligibility for Medicaid before the Affordable Care Act. Since the 1990s, income eligibility for children and pregnant women went up to 300% FPL, and up to 200% FPL for other adults. In 2009, enrollment was capped for childless adults up to 200% of FPL without other categorical eligibility (because of budget issues). In 2013, there were over 157,000 people on the waiting list.
Current Governor Scott Walker was elected in 2011, and he was not excited about the Affordable Care Act. He definitely did not want to support the Medicaid expansion, but as governors have been learning, rejecting lots of money for your state and health insurance for your constituents is not the greatest option. Because Wisconsin had already exceeded the ACA Medicaid thresholds, they were able to get an unusual Section 1115 waiver. Starting in 2014, they stopped capping enrollment for non-elderly adults under 100% of FPL, but cut the people above that income threshold, sending them to the Marketplace to buy a subsidized insurance plan. This provided a political alternative to supporting the ACA while allowing people to be covered somehow. Perhaps less ideal than doing the expansion, but an interesting way to increase access.